Question

In java need help with the TODO sections creating recursive methods

public class CountUpDown
{
    /**
     * countUp - a recursive function that counts up from 1 to n
     *
     * @param n    the integer value to count up to
     */
    private static void countUp(int n)
    {
        // TODO PRELAB
        // IMPLEMENT THIS RECURSIVE METHOD

    }

    /**
     * countDown - a recursive function that counts down from n to 1
     *
     * @param n    the integer value to count down from
     */
    private static void countDown(int n)
    {
        // TODO PRELAB
        // IMPLEMENT THIS RECURSIVE METHOD

    }

    public static void main(String[] args)
    {
        Scanner input = new Scanner(System.in);
        int n = 10;        //default value is 10
        try
        {
            System.out.println("Please enter an integer value greater than 0");
            n = input.nextInt();
            if (n <= 0)
            {
                n = 10;
                throw new Exception();
            }

        }
        catch(InputMismatchException e)
        {
            System.out.println("Could not convert input to an integer");
            System.out.println("Will use 10 as the default value");
        }
        catch(Exception e)
        {
            System.out.println("There was an error with the input value");
            System.out.println("Will use 10 as the default value");
        }

        System.out.println();
        System.out.println("Should count down to 1");
        countDown(n);

        System.out.println();
        System.out.println("Should count up from 1");
        countUp(n);
    }
}

//    Please enter an integer value greater than 0
//        5
//
//        Should count down to 1
//        5
//        4
//        3
//        2
//        1
//
//        Should count up from 1
//        1
//        2
//        3
//        4
//        5

Answer 1

The count up function is..

private static void countUp(int n)
{
if (n == 1)
{
System.out.println(n);
}
else
{
int y = n - 1;
countUp(y);
System.out.println(n);
}
}

The count down function is...

private static void countDown(int n)
{
if (n == 0)
{
return;
}
else
{
System.out.println(n);
countDown(n-1);
if(n==1)

{
System.exit(0);
}

System.out.println(n);
}
}